Old Upper Trof continues to weaken with the remains shearing out to the east today………Looks like a bit of a break Friday, then the chance of thunder returns Saturday and Sunday…..

Thursday August 7, 2014

Posted at 9:37 am by Howard

Friday AM Update:

From Incident Information System

French Fire is now 90% contained! Woo Whoo!

Majority of the heat continues to be in the north half of the incident, the southern portion of the fire consists mostly of isolated heat sources. There are still some areas where ground fire and isolated torching is occurring. Overall the entire fire is cooling off with only the large logs burning out. Helicopters were used to improve operations today. Road closures remain in effect in the fire area. Full Containment by next Tuesday.

WX Discussion:

Local Weather is expected to be partly cloudy this afternoon with Thunderstorms forming over the higher elevated heat source of the Sierra, then blowing off to the east during the later afternoon hours. Today does not look as active over the Mammoth area as the last two days. We are in-between WX systems. Highs today in the mid 70s Light west wind with only very light smoke expected.

Tomorrow Saturday will be increasing effected by an approaching upper low that will spin up as it approaches the central coast. This Mornings 12KM NAM shows a return of southerly flow which will back to the SE by Sunday AM. Monsoon moisture as well as the Dynamic NE quad and upper divergence will return to the Eastern Sierra Saturday for a greater threat of thunder during the afternoon. By Sunday Am, a coupled 80 knot upper jet with the front left quad will take aim over Mono County….For the greatest chance for thunderstorms. The timing is best for Sunday late AM and into the night. So the chance of heavy rain returns to the eastern sierra Sunday PM. By Monday, the upper low kicks NE and a return of a drier SW flow occurs with only isolated showers for the high country and Western Nevada expected. At the moment the drying includes the Sierra as well as Esmeralda County in western NV, especially Monday into Tuesday. Thereafter, the models diverge. The NWS is forecasting dry weather Wednesday into Thursday….. I personally am not as bullish….However they are the experts…I’m just a Dweeb………..

July was a wet month in Mammoth with 1.45 inches of precipitation here at www.mammothweather.com. August began with above normal precip as well as Mammoth picked up any ware between .10 and .30 of an inch of rainfall during thunderstorms yesterday afternoon. That in addition to some light rain last weekend puts the tally up close to 1/2 inch.

Today with a much less dynamic atmosphere, there will be afternoon clouds. However, chances of thunderstorms have diminished significantly. Tomorrow the official forecast is for scattered thunderstorms due to another small upper low moving onshore over Central CA. However, with that said, the new 12Z guidance (GFS-NAM) guidance seems to have lost that upper center for Friday all together, and instead puts the emphasis on another upper low approaching the Bay Area Sunday. By Tuesday morning it is centered over the Golden Gate. This is further north and not as favorable for afternoon convection over Southern Mono County. This favors the Northern Sierra. What we may end up with is just a moderate zephyr and partly cloudy skies along with a few isolated showers mainly east of highway 395. By Tuesday afternoon the upper vort center on the GFS has the VT center over the west side of Tahoe over the Northern Sierra and then sheers the remaining energy to the northeast away from us.

Odds are, we will have a dry SW flow through the next 3 to 5 days and just some afternoon clouds…..Any TSRWS should remain only in the most favorable areas such as east of highway 395 and the Bodie Hills and north. I will update again tomorrow AM, if by chance the models find that elusive Vort Center for Friday!

For you ranchers in the fish lake valley/Oasis area, it looks like the break you have been waiting for has arrived to cut your Alfalfa. Although you may have isolated thunderstorm action, I do not see any extended periods of heavy rain through the middle of next week. I do see the possibility of a SE flow pattern redeveloping the following weekend of the 15th. I will take another look at it all to be sure Friday morning……

The French Fire is now 85% contained and very little smoke is found in the Mammoth area. Barring any flair ups…..we should be out of the woods on this one….

EL Nino: The CPC has lowered the odds for an El Nino to develop this Fall from near 80% to 60% now.

PS…you do not need to have an EL Nino to get a great winter here in Mammoth. It just makes it easier to forecast ahead of time…..